Main Content

length

Number of stored points

collapse all in page

Syntax

length(points)

Description

length(points) returns the number of stored points in the points object.

example

Examples

collapse all

Open Live Script

Read an image.

I = imread("cameraman.tif");

Detect KAZE points from the image.

points = detectKAZEFeatures(I);

Find number of stored points.

numPoints = length(points)
numPoints = 
631

Extract KAZE features from the detected points.

[features,validPoints] = extractFeatures(I,points);

Plot the ten strongest valid extracted points and show their orientations.

imshow(I)
hold on
strongestPoints = selectStrongest(validPoints,10);
plot(strongestPoints,showOrientation=true)
hold off

Figure contains an axes object. The hidden axes object contains 3 objects of type image, line. One or more of the lines displays its values using only markers

Input Arguments

collapse all

Points object,specified as one of the point feature objects described in Point Feature Types. The object contains information about the feature points detected in the input image. To obtain points, use the appropriate detect function that pairs with the point feature type.

Version History

Introduced in R2017b

See Also

Functions

Objects

Topics